Allow Claude to rename the current session programmatically

Feature request

Currently, session naming is a UI-only action — users can rename a conversation manually, but there is no way for Claude itself to set or update the session title during a conversation.

Use case

In agentic workflows (e.g. a ship-it skill that creates a Jira ticket, a branch, and opens a PR), Claude has all the context needed to produce a meaningful session title — typically the branch name or ticket ID (e.g. GO-1234/add-push-notification). Being able to auto-rename the session at that point would make session history genuinely navigable instead of a list of "New conversation" entries.

Proposed solution

Expose session renaming as either:

• A model-callable tool (e.g. set_session_title(title: string)) available during a conversation
• A slash command Claude can invoke (e.g. /rename <title>)
• A hook side-effect that a PostToolUse hook can trigger

Current workaround

None — patching the session file in ~/.claude/ directly is undocumented and fragile.